Species: Canine   |   Classification: Miscellaneous

The atom

  • All chemical elements are made of atoms.
  • Atoms consist of a core (nucleus) of protonswhich are positively charged surrounded by a cloud of electronswith a negative charge.
  • Normally there are the same number of electrons as protons in the atom so that it has no charge overall.
  • Anionis an atom that has lost or gained electrons giving it an overall positive or negative charge respectively.
  • The electrons circle the nucleus in pre-determined orbits (shells).
  • Each shell contains a pre-set number of electrons and each shell can be defined by its energy level.
  • Electrons can move from inner orbits to outer ones but moving between shells requires energy.
  • This energy can be released if the electron moves back to an inner shell.


  • X-rays belong to the group of electromagnetic radiation.
  • They possess the typical characteristics of this group:
    • Travel in straight line (direction can be altered but the new path is also a straight line).
    • Can pass through a vacuum.
    • Travel at a constant velocity (which, in a vacuum, is the velocity of light).
    • Variably absorbed by body tissue.
    • Affect photographic film to produce a latent image.
    • Cause certain substances to fluoresce.
    • Have no electric charge (unaffected by magnetic or electric fields).
    • Can ’ somatic and genetic damage following interaction with living tissue.
    • At any point in the wave there is an oscillating field perpendicular to both the electric field and the direction of the wave.
    • Have the ability to ionize therefore known asionizing radiation.
    • X-rays produce indirect ionization, they interact with matter to produce high energy electrons which interact with atoms ’ ionization.
    • E=h vwhere h=Planck's constant (6.6 x 10*34 J s).
    • Therefore scatter ’ increased E.
    • Aphotonis a quantum (packet) of electromagnetic energy.